Reverse charge on purchase from registered dealer

Dear sir

Plz clarify RCM on agricultural produce 

Will reverse charge attract when a registered dealer/commission agent purchase goods/agricultural crop from farmer.

Thanks

In a case where a composition dealer, purchases goods from Regular Dealer - Is reverse charge applicable i.e.,  Whether composition dealer is liable to pay tax for the goods purchased from regular dealer?

Hi! Can you pleae explain your statement with an example. Also explain the tax treatment if the same is in reverse order